In a recent paper the New Zealandish geologist A. Steiner has made a redefinition of ignimbrite as a descriptive non-genetic term meaning an acid volcanic rock showing gradational, vitroclastic-like textures and characterized by the presence of two contrasting glasses, which are usually devitrified. In indicating the significance of liquid immiscibility in forming of ignimbrites he emphasizes that according to the widespread occurrence of ignimbrites liquid immiscibility is an important phenomenon of igneous petrogenesis.